High water content in dredged silt leads to elevated costs for drying and solidification. By fully utilizing the porous water absorption of Expanded Perlite (EP), we can locally separate free water from the silt, resulting in an uneven water distribution and creating a silt-water separation solidification environment. Experimental results indicate that incorporating EP with silt can effectively enhance the unconfined compressive strength (UCS) of the solidified silt, but the method of incorporation affects the rate of strength increase and pore distribution. The stewing method, which involves pre-mixing EP into the silt and then adding cement after 24 hours, proves most favorable for promoting the solidification effect. After 28 days of curing, the strength of the stewing sample is 1.56 times that of the sample directly solidified with cement after EP incorporation, and 2.15 times that of the sample solidified with cement only. This indicates that the local silt-water separation effect facilitated by EP can effectively enhance the strength of the solidified silt. Meanwhile, hydration heat test results show that EP promotes cement hydration. According to the pore distribution curve and surface morphology images of EP-silt-solidified soil, while EP introduces porosity, it also provides growth space for hydration products, resulting in an embedded bond that forms a solidified soil skeleton between the interface of silt and EP. The method of regulating water content using EP is a physical one, which is convenient and efficient, differing from energy-intensive methods like machinery. Additionally, as a high-silica lightweight aggregate, EP exhibits good compatibility with silt and is environmentally friendly.

Cement displays notable shortcomings in deep soil mixing column (DSM) applications,including columnforming failure in soft soil with a high water content and adverse effects on the environment. In this paper, a curing agent named FHC is introduced, specifically designed for soft soil with high moisture content and composed of GGBS, cement, fly ash, and sodium silicate. FHC was used for laboratory solidification treatment of soft clay with a water content of 80 %. The strength and deformation characteristics of FHCS were studied, and the solidification mechanism was analyzed. The findings show that the 7-day strength of FHCS reached 77 % of its 28-day strength, exhibiting notable early strength characteristics. The alkaline environment created by sodium silicate leads to a significant long-term increase in the strength of FHCS. Fitting a power function to strength, FHC content, and curing age allows for accurate prediction of FHCS strength. The failure strain (epsilon(f)) of FHCS slightly increases with the increase of FHC content, exhibiting pronounced brittleness. The deformation modulus (E-50) of FHCS increases with both the FHC content and age, satisfies with strength as: E-50 = (14 similar to 51)q(u). The quantity of gelling products in FHCS increases with increasing FHC content and age, during which soil particles are progressively enveloped, pores in the soil are filled, and the cross- becomes more flat, leading to a stable and dense structure and subsequent strength enhancement.